Method of making a vacuum cleaner hose



Oct. 12, 1965 R. L. BROWN ETAL METHOD OF MAKING A VACUUM CLEANER HOSE Original Filed Feb. 15, 1961 IN V EN TOR S Rev/noun L 320w Do we f. DOWNEY THEIR ATTORNEY United States Patent Original application Feb. 15, 1961, Ser. No. 89,560. Divided and this application June 25, 1962, Ser. No.

4 Claims. (Cl. 156-143) This application is a division of our copending application Serial No. 89,560 filed February 15, 1961.

Our invention relates to a method of manufacturing hose particularly vacuum cleaner hose in which is incorporated a pair of electric conductors.

In suction hose it is necessary to provide reinforcing means in order to prevent collapse of the hose when subjected to sub-atmospheric pressure and this reinforcing means is usually in the form of a spirally wound steel wire, around which is wrapped a rubberized sheet of material, preferably nylon friction sheeting, to provide the airtight carcass of the hose. In accordance with our invention, a pair of reinforcing wires wound in the form of a double spiral is substituted for the aforesaid single spiral wound wire.

During manufacture of a hose of this general type it is customary to wind a jute cord around the rubberized sheeting in order to hold it in place prior to vulcanizing. However, in accordance with our invention a pair of suitably insulated conductor wires is wound around the outside of the wrapped sheeting in the form of a double spiral, the turns of conductors being spaced between the turns of the reinforcing wires. The conductors are Wound tightly enough so as to pull the sheeting inwardly between the turns of the reinforcing wires, thus forming spiral grooves in which the conductors are disposed.

The foregoing assemblage is then subjected to a high temperature, preferably a steam atmosphere in a device called an autoclave, the heat serving to valcanize the rubberized sheeting so as to bond it to the reinforcing wires and to itself. Thereafter, an outer tubular casing is provided for the purpose of providing an attractive and protective outer surface for the finished hose.

By wrapping the conductors around the outside of the tubular sheet material they, and particularly their insulation, are protected from damage by metallic objects which may be drawn through the hose during use and they are isolated from any liquid which may be drawn into the hose. The conductors are insulated from each other not only by their own insulation, but by the fact that they are separate wires which are spaced from each other at all points. These conductors and their insulation are protected from abrasion against any surface over which the hose is moved by the outer tubular casing.

Further objects and advantages of our invention will be apparent from the following description when considered in connection with the accompanying drawings which form part of the specification and of which;

FIG. 1 is a side view, partially broken away, of a vacuum cleaner hose in accordance with our present invention;

FIG. 2 is a side view on an enlarged scale partially broken away and partially in cross-section showing a portion of the hose illustrated in FIG. 1; and

FIG. 3 is a view similar to FIG. 2, but showing another embodiment of our invention.

Referring to the drawings, reference character designates generally a suction hose secured at one end to one element 12 of a separable coupling and at the other end to a rigid metal tube 14. As is shown more particularly in FIG. 2, hose 10 includes a pair of reinforcing wires 16 and 18 wound in the form of a double spiral by the use of a conventional former or support means notoriously old and well known in the art, one example of which is disclosed by the U.S. Patent No. 2,743,759 to Snow et al. Wrapped around the reinforcing wires is a sheet 20 of airtight rubberized material, preferably nylon friction sheeting. After the sheeting 20 has been wrapped around the spiral reinforcing wires with its opposite edges overlapped to form a seam 21, two conductors 22 and 24 are wound around the sheeting in the spaces substantially midway between adjacent turns of the two respective reinforcing wires, as shown in FIG. 2. The conductors are wound tightly enough to draw the sheeting inwardly between the reinforcing wires so as to form spiral grooves therebetween within which the conductors are located.

During the manufacture of the hose the conductors 22 and 24 thus serve to retain the sheeting 20 wrapped around the spiral reinforcing wires 16 and 18. In this condition the assemblage is subjected to the high temperature of a steam atmosphere in an autoclave. This vulcanizes the rubber present in the sheeting 20, the conductor wires 22 and 24, and by drawing the sheeting radially inward causes it to form a uniform bond with the reinforcing wires 16 and 18 and with itself along the overlapped seam 21 to form a tubular airtight carcass throughout its entire length. These wires are made of steel for strength, but preferably are brass coated in order that the rubber may form a suitable bond therewith. The conductors 22 and 24 are preferably made of copper and each is insulated with an insulation suitable for the service to which the hose is intended to be subjected and capable of withstanding the vulcanizing process in the autoclave. A suitable insulation is Formvar, a trademark name of plastic resins that are formals of polyvinyl alcohol and glass or silicone rubber.

After vulcanizing process has been completed the hose is provided with an outer protective and decorative casing or covering. As shown in the drawings this may consist of braiding 26 which surrounds the sheeting 20 and the conductors 22 and 24. Due to the fact that the conductors are disposed in the spiral groove formed in the sheeting by the tight wrapping of the conductors, they do not form spiral ridges in the braiding 26 and the outer surface of the latter is smooth. This braided covering protects the insulated conductors 22 and 24 from abrasion against any surface over which the hose may be moved, thus eliminating the possibility of damaging the insulation. The two conductors 22 and 24 are insulated from each other not only by the Formvar insulation on each conductor, but also by the fact that they are separated from each other throughout their length and are supported on the insulating surface of the rubberized sheet material 20. This material also separates the conductors from the reinforcing wires 16 and 18 and isolates the conductors from water or other liquid which may pass through the hose. The conductors and their insulation are also protected from damage by sharp metallic objects which may be drawn through the hose.

Any suitable terminals may be provided for the conductors at the ends of the hose. As is shown in FIG. 1, the conductors at the right end of the hose are brought out through the braiding and into a receptacle 28 having a band 30 integral therewith and encircling the hose for securing the receptacle to the latter. The conductors are connected to recessed contacts 32 which are adapted to receive the prongs of a suitable electric plug. At the left end of the hose adjacent the separable connector 12 the conductors are connected to a two-conductor cord 34 provided at its opposite end with a male plug 36.

In use, the hose may be connected to the inlet of a vacuum cleaner by means of the separable connector 12, the plug 36 being engaged with a suitable receptacle on the vacuum cleaner. The rigid tube 14 may be connected to'the hollow handle or wand leading from a suction nozzle provided with a motor-driven brush and having a cord provided with a suitable plug for connection with the receptacle 28. In this way electric power may be supplied to the nozzle through the conductors 22 and 24 in the hose.

The embodiment illustrated in FIG. 3 is similar to that above described, with the exception that a length of tape 38 is wound spirally around the carcass after the conductors 22 and 24 have been wound in place. This tape preferably is made of rubberized sheeting so that during the vulcanizing process the overlapping edges of the tape 38 are vulcanized together and the inner surface of the tape is vulcanized to the outer surface of the sheeting 20.

The purpose of this tape is to further insulate and protect the conductors 22 and 24. As was the case in the first embodiment, an outer decorative covering 26 in the form of a braided tube is provided around the spirally wound tape.

While we have shown and described two more or less specific embodiments of our invention it is to be understood that this has been done for the purpose of illustration only and that the scope of our invention is not to be limited thereby, but is to be determined from the appended claims.

What we claim is:

1. The method of fabricating a suction hose having electric conductors therein which comprises winding a pair of reinforcing wires in a double spiral on a support means, wrapping rubberized sheet material around said spiral to form a carcass, winding a pair of insulated conductors around the outside of said carcass to secure'said sheet material in place, applying heat to vulcanize the rubberized sheet material to the reinforcing wires and insulated conductors to thereby form a'vulcanized carcass, and encasing the vulcanized carcass in an outer covering.

2. The method of fabricating a suction hose having electric conductors therein which comprises winding a pair of reinforcing wires in a double spiral on a supportmeans, wrapping rubberized sheet material around said spiral to form a carcass, winding a pair of insulated conductors tightly around the outside of said carcass to draw the material thereof in between the turns of the reinforcing wires to form spiral grooves of sufficient depth to accommodate said conductors, applying heat to vulcanize the rubberized sheet material to the reinforcing wires and insulated conductors to thereby form a vulcanized carcass, and encasing the vulcanized carcass in an outer covering.

3. The method of fabricating a suction hose having electric conductors therein which comprises winding a pair of reinforcing wires in a double spiral on a support means, wrapping rubberized sheet material around said spiral to form a carcass, winding a pair of insulated conductors around the outside of said carcass to secure said sheet material in place, winding a strip of rubberized tape spirally over said conductors, applying heat to vulcanize the rubberized sheet material to the reinforcing wires and insulated conductors and to vulcanize the rubberized tape to itself and to the sheet material to thereby form a vulcanized carcass, and encasing the vulcanized carcass in an outer covering.

4. The method of fabricating a suction hose having electric conductors therein which comprises winding a pair of reinforcing wires in a double spiral on a support means,

wrapping rubberized sheet material around said spiral to form a carcass, winding a pair of insulated conductors around the outside of said carcass to draw the material thereofin between the turns of the reinforcing wires to formspiral grooves of suflicient depth to accommodate the conductors, winding a strip of rubberized tape spirally over the conductors in said grooves, applying heat to vulcanize the rubberized sheet material to the reinforcing wires and insulated conductors and to vulcanize the rubberized tape to itself and to the sheet material to thereby form a vulcanized carcass, and encasing the vulcanized carcass in an outer covering.

References Cited by the Examiner UNITED STATES PATENTS EARL M. BERGERT, Primary Examiner. 

1. THE METHOD OF FABRICATING A SUCTION HOSE HAVING ELECTRIC CONDUCTORS THEREIN WHICH COMPRISES WINDING A PAIR OF REINFORCING WIRES IN A DOUBLE SPRIAL ON A SUPPORT MEANS, WRAPPING RUBBERIZED SHEET MATERIAL AROUND SAID SPIRAL TO FORM A CARCASS, WINDING A PAIR OF INSULATED CONDUCTORS AROUND THE OUTSIDE OF SAID CARCASS TO SECURE SAID SHEET MATERIAL IN PLACE, APPLYING HEAT TO VULCANIZE THE RUBBERIZED SHEET MATERIAL TO THE REINFORCING WIRES AND INSULATED CONDUCTORS TO THEREBY FORM A VULCANIZED CARCASS, AND ENCASING THE VULCANIZED CARCASS IN AN OUTER COVERING. 